Details for Patent: 7,566,729

Which drugs does patent 7,566,729 protect, and when does it expire?

Patent 7,566,729 protects ESBRIET and is included in two NDAs.

This patent has sixty-four patent family members in thirty-nine countries.

Summary for Patent: 7,566,729

Title:	Modifying pirfenidone treatment for patients with atypical liver function
Abstract:	Methods are provided for administering pirfenidone to a patient that has exhibited abnormal biomarkers of liver function in response to pirfenidone administration. The methods include administering to a patient pirfenidone at doses lower than the full target dosage for a time period, followed by administering to the patient pirfenidone at the full target dosage.
Inventor(s):	Bradford; Williamson Ziegler (Ross, CA), Szwarcberg; Javier (San Francisco, CA)
Assignee:	Intermune, Inc. (Brisbane, CA)
Application Number:	12/428,393
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,566,729
Patent Claim Types: see list of patent claims	Use;

United States Patent 7,566,729: A Detailed Analysis of Scope, Claims, and Patent Landscape

Introduction

The United States Patent 7,566,729, held by Genentech, Inc., is a significant patent in the pharmaceutical sector, particularly related to the treatment of idiopathic pulmonary fibrosis (IPF) using pirfenidone. This analysis will delve into the scope, claims, and the broader patent landscape surrounding this patent.

Background of the Patent

The patent in question, U.S. Patent 7,566,729, is part of a series of patents related to the administration of pirfenidone, a drug used to treat IPF. Pirfenidone was first studied in the 1970s and gained FDA approval in the United States in 2014[1].

Scope of the Patent

The patent does not claim pirfenidone itself or its use in treating IPF. Instead, it focuses on specific methods of administering pirfenidone, particularly in relation to managing liver function and drug-drug interactions.

Liver Function Test (LFT) Patents

The LFT patents, including U.S. Patent 7,566,729, describe methods for adjusting the dosage of pirfenidone based on liver function biomarkers. For example, the patent includes claims for administering pirfenidone at lower doses if a patient exhibits grade 2 abnormalities in liver function biomarkers such as alanine transaminase and aspartate transaminase. The dosage is adjusted to ensure the patient's liver function remains within safe limits[4].

Claim Construction

A key aspect of this patent is the claim construction, particularly the term "Grade 2 abnormality in one or more biomarkers of liver function." In the case of Genentech, Inc. v. Aurobindo Pharma Limited, the District Court for the District of Delaware held that this term was not indefinite, adopting the plaintiffs' proposed claim construction[2].

Claims Analysis

Representative Claims

Claim 1 of the '729 patent is illustrative:

• Administering pirfenidone to a patient with IPF who has exhibited a grade 2 abnormality in one or more biomarkers of liver function.
• The administration involves initial doses lower than 2400 mg/day, followed by doses of 2400 mg/day or 2403 mg/day, with the biomarkers including alanine transaminase and aspartate transaminase[4].

Dependency of Claims

The claims in this patent are often dependent on parent claims, which incorporate the specific conditions and adjustments for pirfenidone administration. This structure ensures that the claims are narrowly tailored to the specific methods of managing liver function and drug interactions[4].

Patent Landscape and Litigation

Hatch-Waxman Act and ANDA Proceedings

The patent is part of the broader landscape of Hatch-Waxman litigation, which governs the approval and litigation process for generic drugs. Under the Hatch-Waxman Act, generic manufacturers can file an Abbreviated New Drug Application (ANDA) challenging the validity of brand patents. In the case of Genentech, Inc. v. Sandoz Inc., Sandoz filed ANDAs to market a generic version of pirfenidone, leading to a patent infringement suit by Genentech[1].

Federal Circuit Decision

The Federal Circuit affirmed the District Court's decision that the LFT claims were unpatentable for obviousness. The court found that the methods described in the patent were routine practices for clinicians and were obvious in light of prior art, such as the Azuma reference and the PIRESPA label[1].

Relevance of Past Conduct

In this litigation, the Federal Circuit clarified that past conduct is relevant to determining future infringement. This means that evidence of actual physician practice and past dosing regimens can be used to predict how a generic drug would be used in the future, which is crucial for assessing induced infringement[1][4].

Patent Quality and Scope Metrics

Metrics for Measuring Patent Scope

Research on patent scope suggests that metrics such as independent claim length and independent claim count can be used to measure the breadth and clarity of patent claims. Narrower claims, like those in U.S. Patent 7,566,729, are often associated with a higher probability of grant and a shorter examination process[3].

Criticisms of Broad and Unclear Claims

The broader debate on patent quality highlights concerns about overly broad and unclear claims, which can impede innovation by increasing licensing and litigation costs. However, the claims in U.S. Patent 7,566,729 are specific and narrowly tailored, avoiding such criticisms[3].

Industry Impact and Expert Insights

Impact on Generic Drug Manufacturers

The decision in Genentech, Inc. v. Sandoz Inc. has significant implications for generic drug manufacturers. It underscores the importance of demonstrating that a generic product will not induce infringement of brand patents, particularly when the generic product's label and proposed use are scrutinized[1].

Expert Views

Industry experts emphasize the need for clear and specific claim construction to avoid legal challenges. For example, Kyu Yun Kim and Thomas Lee Irving from Finnegan note the importance of defining terms consistently within the patent specification to avoid indefiniteness issues[2].

Key Takeaways

• Specific Claims: The patent claims specific methods for administering pirfenidone based on liver function biomarkers.
• Claim Construction: The term "Grade 2 abnormality in one or more biomarkers of liver function" was found to be definite.
• Litigation Outcome: The Federal Circuit affirmed the invalidity of the LFT claims due to obviousness.
• Past Conduct Relevance: Past conduct is relevant for determining future infringement.
• Patent Quality Metrics: Narrower claims are associated with higher grant probabilities and shorter examination processes.

FAQs

What is the main focus of U.S. Patent 7,566,729?

The main focus of U.S. Patent 7,566,729 is on specific methods for administering pirfenidone to patients with idiopathic pulmonary fibrosis (IPF), particularly in relation to managing liver function.

How did the Federal Circuit decide on the validity of the LFT claims?

The Federal Circuit found the LFT claims unpatentable for obviousness, as the methods described were routine practices for clinicians and obvious in light of prior art.

What is the significance of past conduct in determining infringement?

Past conduct is relevant to determining future infringement, as it helps predict how a generic drug would be used based on evidence of actual physician practice and past dosing regimens.

How do metrics like independent claim length affect patent scope?

Narrower claims, as measured by independent claim length, are associated with a higher probability of grant and a shorter examination process.

What are the implications for generic drug manufacturers from the Genentech, Inc. v. Sandoz Inc. decision?

The decision emphasizes the need for generic manufacturers to demonstrate that their product will not induce infringement of brand patents, particularly through careful examination of the generic product's label and proposed use.

Sources

1. PCK IP: Past Conduct Deemed Relevant to Infringement in ANDA Proceedings[1].
2. Finnegan: A Success Story (So Far!) in Drafting a Patent Application[2].
3. Hoover Institution: Patent Claims and Patent Scope[3].
4. Federal Circuit: GENENTECH, INC. v. SANDOZ INC.[4].
5. Patent Docs: Genentech, Inc. v. Sandoz Inc. (Fed. Cir. 2022)[5].

Drugs Protected by US Patent 7,566,729

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Genentech Inc	ESBRIET	pirfenidone	CAPSULE;ORAL	022535-001	Oct 15, 2014	AB	RX	Yes	Yes	7,566,729					DOSAGE MODIFICATION FOLLOWING ELEVATED LIVER ENZYMES IN TREATMENT OF IDIOPATHIC PULMONARY FIBROSIS
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-001	Jan 11, 2017	AB	RX	Yes	No	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY DISCONTINUING PIRFENIDONE UNTIL BIOMARKERS ARE WITHIN LIMITS, THEN SUB-2400MG/DAY DOSE, THEN FULL DAILY DOSE IN TREATMENT OF IPF
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-001	Jan 11, 2017	AB	RX	Yes	No	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY ADMINISTERING SUB-2400 MG/DAY DOSE THEN FULL DAY DAILY DOSE IN TREATMENT OF IPF
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-002	Jan 11, 2017		DISCN	Yes	No	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY ADMINISTERING SUB-2400MG/DAY DOSE THEN FULL DAILY DOSE IN TREATMENT OF IPF
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-002	Jan 11, 2017		DISCN	Yes	No	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY DISCONTINUING PIRFENIDONE UNTIL BIOMARKERS ARE WITHIN NORMAL LIMITS, THEN SUB-2400MG/DAY DOSE, THEN FULL DAILY DOSE IN TREATMENT OF IPF
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-003	Jan 11, 2017	AB	RX	Yes	Yes	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY DISCONTINUING PIRFENIDONE UNTIL BIOMARKERS ARE WITHIN LIMITS, THEN SUB-2400MG/DAY DOSE, THEN FULL DAILY DOSE IN TREATMENT OF IPF
Genentech Inc	ESBRIET	pirfenidone	TABLET;ORAL	208780-003	Jan 11, 2017	AB	RX	Yes	Yes	7,566,729					DOSAGE MODIFICATION FOLLOWING GRADE 2 ABNORMALITY IN LIVER FUNCTION BIOMARKER AFTER PIRFENIDONE ADMINISTRATION, BY ADMINISTERING SUB-2400 MG/DAY DOSE THEN FULL DAY DAILY DOSE IN TREATMENT OF IPF

International Family Members for US Patent 7,566,729

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	E503480
Australia	2009313302
Australia	2010212371
Australia	2011200385
Australia	2012205256
Brazil	PI0921022
Canada	2709997